Pizza Shop That Pays It Forward With Handwritten Notes Gets Giant Surprise on 'GMA'

— -- Welcome to Rosa’s Fresh Pizza, serving up some of the best $1 slices in all of Philadelphia. But when you step out of the kitchen, it doesn’t take long to realize the secret ingredient isn’t in the sauce. Instead, it’s on the wall, written in thousands of handwritten messages.

“One day a customer came in and offered to pre-purchase a slice for someone in need that might come in short of the dollar,” Mason Wartman, owner of Rosa’s Fresh Pizza, told ABC News. “I ran out [and] got a Post-It note, put one up to remind myself and the employees that we could give one away and since then, we’ve kind of covered our walls with Post-It notes.”

The simple idea has been an overwhelming hit. Each note of hope is worth a free slice.

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It’s something the 27-year-old owner never dreamed of when he left his job on Wall Street more than two years ago.

His favorite notes are not ones for a free pie, but rather ones of gratitude.

“It’s a paper plate that a homeless recipient wrote on,” Wartman explained. “Because of you, I ate off this plate. It is the only thing I ate all day. I am a homeless veteran and get treated rudely when I ask for help. Rosa’s treats me with respect. Truly a blessing. Thank you.”

Wartman added that people “get to come in here, sit down, relax and then go back out and try to build their life back up and it’s great to provide that to them.”

But perhaps even more special are the customers who were once down on their luck and are now returning to pay it forward themselves, like 38-year-old Eddie Dunn.

Just a year ago Dunn was at rock bottom, often begging for change right across the street from Rosa's.

“Rosa’s offered the opportunity for me to have a meal on days when I wouldn’t have been able to,” said Dunn. “Whenever people were kind to me like Mason, I felt human.”

Dunn is thrilled to not only be able to pay for his slice now, but also be able to buy one for someone else.

“The feeling of giving back to others when, you know, you were on the other end of the scope at one point, it’s indescribable," he explained.

It’s a sentiment Wartman’s mother, who the shop is named after, couldn’t agree with more.

“He’s a good kid,” said Rosa Wartman, holding back tears.

“Each little thing that you do really can have a tremendous impact and huge ripple effect,” said Dunn. “It makes me excited for the future.”

But today, Wartman was the receipt of some heartfelt giving.

The “Good Morning America” staff surprised the pizza store owner with $535 and more handwritten Post-It notes for him to add to his collection as part of the show’s “Thank You, America” series honoring those who give back and make a real difference.

That wasn’t all.

The RetailMeNot app, as part of its new “Save It Forward” program, also donated $2,000 to Wartman’s pizza shop.

“This is so kind of you. Thank you so much. Wow,” Wartman said, covering his mouth in shock.

And here’s the icing on the cake: As Wartman opened a pizza box on air, he learned that Disney was sending him and three of his guests for a five day trip Aulani -- Disney’s award-winning resort and spa in Hawaii.

“Wow, thank you,” he said. “I’m speechless.”

The Walt Disney Company is the parent company of ABC News.